Let say the two train cars are of masses
and 
now if the speed of two cars are
and 
then we can say that the momentum of two cars before they collide is given by

here two cars are moving in opposite direction so we can say that the net momentum is subtraction of two cars momentum.
Now since in these two car motion there is no external force on them while they collide
So the momentum of two cars are always conserved.
hence we can say that the final momentum of two cars will be same after collision as it is before collision

Habitat fragmentation is a cost of urban development.
Option: A
Explanation:
Though from the view point or perspective of up gradation and development urban development is much needed but in cost of habitat fragmentation which feels very bitter. As habitat fragmentation leads to the loss of habitat, disruption of ecological cycle and environmental equilibrium.
Actually in the name of urban development we the human use our bread giver environment in a wrong way which causes natural disasters in long run. Animals become endangered , vulnerable and extinct with passage of time. Because they forced to enter into human settlements.
Answer:
7 / 1
Explanation:
The ratio of their amplitude = one-seventh and the ratio of their amplitude = the ratio of their wavelength
Ax / Ay = λx / λy = 1 / 7
λy / λx = 7 / 1
5m/s
Explanation:
Given parameters:
Mass of ball = 0.1kg
Force on the ball = 5N
time taken = 0.1s
Unknown:
final speed of the ball = ?
Solution:
According to newton's second law "the net force on a body is the product of its mass and acceleration".
Force = mass x acceleration equation 1
Acceleration =
V is the final velocity
U is the initial velocity
T is the time taken
U = O since it is a stationary body;
a = 
Input "a" into equation 1
F = m x 
5 = 0.1 x 
V = 5m/s
learn more:
Newton's laws brainly.com/question/11411375
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